Mobile crusher units of the type described hereinabove are needed to reduce loose material such as ore, rock, coal or oil slate to a desired grain size.
The German DE 36 08 789 C2 describes a mobile crusher unit having a supporting framework that receives at least one crusher, and that can be lifted and relocated, in accordance with the advance of the removal of material, by a transport mechanism, preferably a walking-leg system or an extendable crawler or wheel undercarriage, and having at least one charging device which is associated with one crusher, and having a receiving hopper for the loose material delivered by freely transporting loading machines such as wheel loaders or excavators, and having a conveyor which feeds the loose material to a transfer hopper of the crusher. The feeding device is required to be mounted in an arrangement swivable around a vertical axis at the supporting framework even during working mode.
Preferably used as crushers are roller-type crushers, -impact crushers, swing-hammer crushers, cone crushers, jaw crushers or gyratory crushers. Installed downstream of the crusher is a discharge conveyor unit which is composed of a discharge conveyor situated beneath the crusher and a dumping conveyor co-acting with the discharge conveyor, with it being possible for the latter unit to be of a mobile configuration with regard to the supporting framework. An embodiment of this kind has a drawback in that it has a relatively large mass owing to the use of the additional discharge conveyor. This additional discharge conveyor requires a drive and maintenance. Moreover, implementing this discharge conveyor adds on the weight of the mobile crusher unit, which is to be considered in the layout of the undercarriage motor power. To solve the task of increasing the economic efficiency of a mobile crusher, and more particularly to diminish the need for service and maintenance and to improve its adaptability to different working conditions, WO 2004/087324 proposes to install downstream of the crusher unit only one dumping conveyor unit which is used both for the discharge and for the dumping procedure, and which in terms of the supporting framework is designed and built as a component group that is swingable in horizontal and vertical direction. Both the feed conveyor unit and the dumping conveyor unit can be configured as a plate-type belt, chain conveyor or belt conveyor. The swing movements of the dumping conveyor unit should be triggered by means of any optional drive, more particularly by means of hydraulic or electro-mechanical drives.
These crusher units or similar ones are comprised of a traveling gear which carries a bogie on which the supporting framework is mounted in a pivotable arrangement. A disadvantage of such a structure is its relatively great construction height which necessitates a correspondingly long feed conveyor whose lower position is determined by the fact that the material to be crushed is discharged from wheel loaders, excavators or dumping trucks, for example. Another drawback lies in the high mass resulting hereof.
Out of AT 388 968 B is known a portable crusher unit for transporting the material over feeding hoppers, sieves, first conveyors and crushing devises to the last conveyor. All these elements are mounted on a common frame, which contains means of crawler undercarriage.